To Stop Nightmares:
Lemon Verbena ( Lippia citriodora )
Place this herb in a pouch and place it under your pillow or place some in your pillowcase to hinder the dream process
Betony ( Betonica officinalis )
Place Betony in a pouch under your pillow while you sleep or inside your pillowcase to block nightmares.
Anise ( Pimpinella anisum )
Place herb in a pouch and hang it on your headboard. Also place some in your pillowcase and under your pillow to halt bad dreams and nightmares
Flax ( Linum usitatissimum ) mixed with Mustard ( Brassica spp. )
Mix a handful of flax with a handful of mustard together and place some seeds on your night stand. Place the rest in a pouch and lay it under your pillow or in your pillowcase

I'm not really sure I put stock in the website linked because it's rather generic and some of the links listed in there are outdated (I'm also not a fan of dream dictionaries by sheer principal of that's laziness for dream work).

There are studies that show our sense of smell affects our dreams (this can be looked up), so if you want to stop nightmares, use more sweet or enticing scents and avoid scents you don't like. Personally, I think eye pillows with herbs are perfect for this. They can be found in the store set up on this website, but you can also make your own if you had the skills for it.

I drink a cup of soothing apple spiced yea, or chocolate Chi tea. It always helps to be, honest.

I heard that putting a damp warm cloth on your face can help, as Well as lavender smells. Keep your temperature warm but not hit, cold but not so your freezing or wrapping yourself into the blankets. Keep it average warm.

using a nice smelling pillow spray and maybe making a lavender perfume to spray the room at night may also help! I also recommend maybe a protection spray for your bed. I had gotten a protection spray from whole foods :) If you would like more information on it just feel free to ask me.